* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

#canvas {
    display: block;
}

#tip {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    overflow-y: auto;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
    color: grey;
    border-bottom: 1px solid grey;
    padding: 1em;
}

#tip::-webkit-scrollbar {
    display: none;
}